What this controller is and what the 50ms sampling means for your loop
The PXF4ACC2-0VVA1 is a self-tuning 1/16 DIN (48 x 48mm) compact temperature and process controller with a 50ms sampling speed. The self-tuning algorithm auto-sets the P, I, and D terms on startup, which saves the commissioning engineer a manual Ziegler-Nichols run on the first power-up.
The 1/16 DIN (48 x 48mm) cutout is the standard panel-mount footprint for temperature controllers — fits the same hole as every other 1/16 DIN unit on the market, so no panel rework if you're swapping out an older controller. The compact depth leaves room behind the panel for wiring duct and the SSR heatsink.